JP4174124B2 - Surface modification method using fluorine-containing epoxy resin composition, ink jet recording head, ink jet recording apparatus - Google Patents

Description

Ｒは、脂環式エポキシ基を有する単量体を結合する脂肪族の残基である。
【００２７】
また、本発明に用いる上記含フッ素エポキシ樹脂としては、下記一般式（Ａ−２）で表わされるエポキシ化合物が好ましく用いられる。
【００２８】
【外８】

【００２９】
また、本発明に用いる上記含フッ素エポキシ樹脂としては、下記一般式（Ａ−３）で表わされるエポキシ重合体が好ましく用いられる。
【００３０】
【外９】

【００３１】
また、本発明に用いる上記含フッ素エポキシ樹脂としては、下記一般式（Ａ−４）で表わされるエポキシ重合体が好ましく用いられる。
【００３２】
【外１０】

【００３３】
また、本発明に用いる上記含フッ素エポキシ樹脂としては、下記一般式（Ａ−５）で表わされるエポキシ重合体が好ましく用いられる。
【００３４】
【外１１】

【００３５】
本発明の含フッ素エポキシ樹脂組成物には、必要に応じて、さらに相溶化剤として下記一般式（Ｃ−１）または（Ｃ−２）で表わされる化合物の少なくとも１種を含有させることができる。
【００３６】
【外１２】

【００３７】
また、本発明は、上記本発明の含フッ素エポキシ樹脂組成物を基材に塗布、乾燥する第１の工程、マスクを介して活性エネルギー線をパターン状に照射する第２の工程、組成物を溶解しうる液体にて活性エネルギー線の非照射部分を溶解除去する第３の工程、必要に応じてポストキュアを施す第４の工程の順序にて、基材に選択的に表面処理を行うことを特徴とする表面処理方法である。
【００３８】
また、本発明は、上記本発明の含有フッ素エポキシ樹脂組成物を基材に塗布、乾燥する第１の工程、熱或いは活性エネルギー線の照射によって上記組成物全面の重合硬化を行う第２の工程、崩壊性の活性エネルギー線を選択的に照射することによって上記硬化した組成物の選択的な除去を行う第３の工程、必要に応じてポストキュアを施す第４の工程、の順序にて、基材に選択的に表面処理を行うことを特徴とする表面処理方法である。
【００４０】
本発明の樹脂組成物はエポキシ樹脂系であるので、各種部材への密着性に優れ、比較的低温でも硬化可能であり、構造物としての物性にも優れた硬化物を提供出来る。さらに末端にパーフロロ基を有するエポキシ化合物が含有されていることで、水溶性有機溶剤、特に、極性有機溶剤に対する耐性が大幅に向上している。そして、相溶化剤の作用によって成分間の共溶性を与え、材料構成の範囲を広くすることができる。
【００４１】
本発明の含フッ素エポキシ樹脂組成物は、極性有機溶剤のように撥水剤の密着性を損なう成分を含む溶液や物質との接触機会のある場所に適用する材料として有用である。そのような箇所に用いる撥水剤または撥水性塗料として、特に、インクジェット記録ヘッドの吐出口面の撥水、撥インク処理には好適である。
【００４２】
本発明のインクジェット記録装置においては、光重合性を利用した選択的な表面改質を用いることで処理精度に優れ、特定の材料を用いて硬化膜を構成することから固体強度、摩擦強度、に優れた撥水あるいは撥インク性部を有することになる。
【００４３】
【発明の実施の形態】
以下、本発明を詳細に説明する。
【００４４】
本発明の含フッ素エポキシ樹脂組成物に用いる含フッ素エポキシ樹脂は、１分中に１個以上のパーフロロアルキル基と２個以上のエポキシ基を有しており、エポキシ基が反応しても分子の比較的外側にパーフロロアルキル基があるため樹脂の表面はフッ素原子の高い密度が保たれる。これによって内部は固い樹脂層でありながら表面は撥水、撥油、撥インク性を示す層形成が可能となると考えられる。
【００４５】
本発明において、上記含フッ素エポキシ樹脂としては、好ましくは下記一般式（Ａ−１）〜（Ａ−２）で表わされるエポキシ化合物、または（Ａ−３）〜（Ａ−５）で表わされるエポキシ重合体の少なくとも１種が好ましく用いられる。ここで、エポキシ化合物とはオリゴマーよりなる化合物をいい、エポキシ重合体とはオリゴマーを除く重合体をいう。
【００４６】
【外１３】

Ｒは、脂環式エポキシ基を有する単量体を結合する脂肪族の残基である。
【００４７】
【外１４】

【００４８】
【外１５】

【００４９】
これらのうち、一般式（Ａ−３）で表されるエポキシ重合体は重合性が低いが、エステル基を持たないので耐水性、加水分解性において優れた塗膜となることが期待される。
【００５０】
また、高重合体であるエポキシ重合体に、エポキシ化合物を併用することにより組成物の塗布適性を高め、溶剤蒸発後の乾燥性を高め、乾燥塗膜としての作業性を向上させる。すなわち、エポキシ化合物はバインダーとして機能する。従って、エポキシ化合物を併用することは、パターン状の露光作業を施す上で好ましい。この際の両者の比率は、それぞれの軟化点、ガラス転移温度を考慮して適宜決定すればよいが、エポキシ化合物：エポキシ重合体＝１０：９０〜９０：１０（重量比）の範囲が好ましい。
【００５１】
上記一般式（Ａ−１）で表わされる化合物の具体例としては、例えば下記化合物が挙げられる。
【００５２】
【外１６】

【００５３】
また、上記一般式（Ａ−２）で表わされる化合物の具体例としては、例えば下記化合物が挙げられる。
【００５４】
【外１７】

【００５５】
また、上記一般式（Ａ−３）で表わされる化合物の具体例としては、例えば下記化合物が挙げられる。
【００５６】
【外１８】

重合させて得られる、数平均分子量６０００のビニル重合体（Ａ−３−１）。
【００５７】
【外１９】

重合させて得られる、数平均分子量８０００のビニル重合体（Ａ−３−２）。
【００５８】
また、上記一般式（Ａ−４）で表わされる化合物の具体例としては、例えば下記化合物が挙げられる。
【００５９】
【外２０】

【００６０】
また、上記一般式（Ａ−５）で表わされる化合物の具体例としては、例えば下記化合物が挙げられる。
【００６１】
【外２１】

【００６２】
本発明のエポキシ樹脂組成物には、それを硬化させるための触媒としてカチオン重合触媒（重合開始剤）を含有している。そのような目的に用いる化合物としては、エポキシ樹脂の硬化剤として知られている物質から選択される。本発明の組成物はエポキシ樹脂組成物であるから、芳香族及び脂肪族アミン類、酸無水物類を添加して加熱硬化によって重合させる事が可能である。しかし本発明では特に低温硬化が可能となるところの活性エネルギー線によって賦活化されるルイス酸のオニウム塩に対して反応性が高くなるように設計されており、フォトリソグラフィーによって選択的に表面処理を行う為に、また高温に保持することが困難な基材に対して表面改質を行うのに好適である。本発明に用いるカチオン重合触媒として好ましくは、ビス（４−ｔｅｒｔ−ブチルフェニル）ヨードニウム塩や、下記構造式で示される「オプトマ−ＳＰ−１５０」、「オプトマ−ＳＰ１７０」（旭電化工業社製）などを使用する。
【００６３】
【外２２】

【００６４】
また、下記構造式で示される「イルガキュア２６１」（チバスペシャルティー社製）等を使用する事が出来る。
【００６５】
【外２３】

【００６６】
本発明の含フッ素エポキシ樹脂組成物には、必要に応じて、さらに相溶化剤として下記一般式（Ｃ−１）または（Ｃ−２）で表わされる化合物の少なくとも１種を含有させる事ができる。
【００６７】
【外２４】

【００６８】
上記相溶化剤の具体例としては、例えば下記構造式で表わされる化合物が挙げられる。
【００６９】
【外２５】

【００７０】
上記相溶化剤は、フッ素原子を有するものの、フロロメチル基を主体としており、鎖長が短いため分子としての表面エネルギー低下作用は小さく、撥水、撥インク性が大きくない。しかしながら、含フッ素エポキシ樹脂とカチオン重合触媒との相溶性を高めるためには有効である。即ち、本発明において上記相溶化剤を併用する場合とは、カチオン重合触媒であるルイス酸のオニウム塩は極性が高いので、用いる含フッ素エポキシ樹脂との相溶性が悪い、塗布する際のレベリング性が得難いなどの実用的な困難を克服する必要がある、等の場合である。
【００７１】
本発明のエポキシ樹脂組成物は、基本的に
Ａ：含フッ素エポキシ樹脂
Ｂ：カチオン重合触媒、及び必要に応じて
Ｃ：相溶化剤、
を含有する。これらＡ，Ｂ，Ｃ，の各成分の組成物中における好ましい配合割合は以下の通りである。
【００７２】
成分Ｂが、エポキシ樹脂成分（成分Ｃを用いない場合には成分Ａ、成分Ｃを併用する場合には成分Ａと成分Ｃの合計）の合計量１００重量部に対して、０．１重量部乃至１０重量部の範囲である。比率の範囲は、層の厚さ、要求されるパターンの精密さ、重合した塗膜の架橋度、現像処理を行う場合には現像の安定性、単に硬化処理のみを行う場合には反応速度、などの要素から決定される。そのような要素を考慮したカチオン重合触媒の通常の使用量は、エポキシ樹脂成分の合計量１００重量部に対して、０．１〜７重量部、より好ましくは、０．３〜５重量部である。
【００７３】
相溶化剤である成分Ｃを併用して用いる場合は、成分Ａ：成分Ｃ＝１００：１０〜１００：１００（重量比）の範囲である。即ち成分Ａは、エポキシ樹脂成分中５０重量％以上でなければならない。
【００７４】
本発明の組成物の構成例を以下に例示する。以下比率は固形分の重量比率を示す。
（組成物例１）Ａ−１−１：Ｂ−１＝９６：４
（組成物例２）Ａ−１−２：Ｂ−１＝９４：６
（組成物例３）Ａ−２−１：Ａ−３−１：Ｂ−２＝４８：４８：４
（組成物例４）Ａ−２−２：Ａ−４−１：Ｂ−１＝３０：６３：７
（組成物例５）Ａ−１−１：Ａ−５−１：Ｂ−２＝３５：６０：５
（組成物例６）Ａ−１−２：Ａ−４−２：Ｂ−１：Ｃ−１（ｐ＝１＝９０：１０：２５：４
（組成物例７）Ａ−２−１：Ａ−３−２：Ｂ−１：Ｃ−２（ｑ＝１＝２５：５５：２０：１
（組成物例８）Ａ−２ー２：Ａ−５−１：Ｂ−１：Ｃ−２（ｑ＝１＝２５：４５：３０：０．５
（組成物例９）Ａ−２−１：Ｂ−１＝９４：６
（組成物例１０）Ａ−２−２：Ｂ−１＝９７：３
【００７５】
本発明の含フッ素エポキシ樹脂組成物には他の重合体を必要に応じて添加することが出来る。例えば、本発明の組成物の塗布適性を高め、溶剤蒸発後の乾燥性を高める乾燥塗膜としての作業性を向上させる機能も与えるもので、バインダーとして機能する重合体を用いることができる。このようなバインダー性の物質の併用は、本発明の組成物をパターン状に露光して所望のパターン形状とする場合に好ましい。
【００７６】
本発明の含フッ素エポキシ樹脂組成物に添加し得るバインダーポリマーとしては、脂環式エポキシ樹脂オリゴマー、フッ素原子団は持たないが側鎖にエポキシ基を持ったアクリルモノマーを共重合したアクリル樹脂、側鎖にエポキシ基を有する脂環式炭化水素基を有するビニルモノマーを重合したビニルポリマー、側鎖にエポキシ基を有する脂環式炭化水素基を有するポリエーテルポリマー（例えば、ダイセル化学工業社製「ＥＨＰＥ３１５０」）などが、それ自体も架橋反応に関与しうるエポキシポリマーとして最適である。このようなエポキシ基を持たない重合体を使用する場合には、それが適用される用途に応じた物性調製を意図して選択する。そうした物質としては、例えばビスフェノール型エポキシ樹脂の重合体である、ユニオンカーバイド社製の「ＰＫＨＣ」や「ＰＫＨＪ」、エチレン／酢酸ビニル共重合体、フェノール樹脂、ポリカーボネート樹脂、ポリエステル樹脂、ポリアミド樹脂、可溶性ポリイミド樹脂などの汎用の塗料用高分子化合物が使用可能である。
【００７７】
尚、本発明の組成物において、このような他の重合体を併用する場合においては、成分Ａと成分Ｃの重量比率は、成分Ａ：成分Ｃ＝１００：１０〜１００：１００（重量比）である。また成分Ｂは、バインダーポリマーを含む組成物全量（１００重量部）中に、０．１〜１０重量部の割合で含有させる。
【００７８】
本発明において組成物を用いる際の具体的な方法に関して、その方法を例示する。活性エネルギー線硬化を行う場合には、前記したように、触媒としてルイス酸を光によって放出する光カチオン重合触媒を添加して用いる。加熱硬化する場合には、三弗化硼素アミン触媒などのルイス酸を添加して用いてもよい。
【００７９】
〈塗膜形成方法〉
本発明の含フッ素エポキシ樹脂組成物は、芳香族系、脂肪族炭化水素系、エステル系、エーテル系、フッ素系溶剤等、有機溶剤中に溶解した状態で用いられる。塗布の膜厚が数μｍと小さい場合には、ロールコーター、スピンコーター、スプレイコーターなどの通常の精密塗布装置を用いることが出来る。
【００８０】
パターン状に表面処理を施す第１の方法は、本発明の含フッ素エポキシ樹脂組成物を基材（被処理対象）に塗布し、乾燥する第１の工程、マスクを用いて活性エネルギー線をパターン状に照射して上記組成物を選択的に硬化させる第２の工程、次いで現像液を用いた現像処理により、第２の工程における活性エネルギー線の非照射部分を溶解除去する第３の工程、を順次行う事によって達成される。基本的な工程はフォトリソグラフィーと同じであるが、現像液としては、樹脂組成物に適した溶剤を選択することが必要である。現像液としては芳香族炭化水素類、ケトン類、エステル類、グリコールエーテル類など及びそれらの混合物を使用する。樹脂組成物の反応の完結を期す為に、現像後に加熱、活性エネルギー線の照射（第４の工程）をさらに行うことが望ましい。
【００８１】
パターン状に表面処理を施す第２の方法は、本発明の含フッ素エポキシ樹脂組成物を基材に塗布し、乾燥する第１の工程、重合を促す熱或いは活性エネルギー線の全面照射により硬化を行う第２の工程、硬化部の所望の部位を選択的に除去するように、崩壊性の活性エネルギー線を照射する第３の工程、を順次施すことによって行う。
【００８２】
第２の方法においても反応を完結させるためには、いずれかの段階で熱処理、重合性の活性エネルギー線の照射（第４の工程）を行うことが望ましい。
【００８３】
上記重合を促す活性エネルギー線としては、波長が２５０〜４８０ｎｍの光を豊富に含む紫外線源が用いられる。また崩壊性の活性エネルギー線としては、波長が２１０ｎｍ以下の光、エキサイマーレーザーなどが用いられる。
【００８４】
このようにして本発明の含フッ素エポキシ樹脂組成物は、極性有機溶剤のように撥水剤の密着性を損なう成分を含む溶液や物質との接触機会のある場所に適用する撥水剤または撥水性塗料として、さらには、インクジェット記録ヘッドの吐出口面の撥水、撥インク、処理を好適に行うことが出来る。
【００８５】
本発明の表面改質方法によれば、基材への密着性、表面の硬度に優れた撥水、撥油処理が行えるので、耐久性に優れた改質が行える。
【００８６】
インクジェット記録ヘッドにおける応用としては、吐出口表面を本発明の組成物を用いて処理することによって、インクの強固な付着が起きず、クリーニング処理によって容易に拭き取れる離型性のよい表面が形成される。インクジェット記録ヘッドに搭載されているクリーニング機構の多くは、ゴムのブレードで拭き取る、ポンプで吸引する、記録紙外の位置で空吐出を行う、などである。しかしこれらのいずれの方法であれ、吐出圧によって引き出されたインク柱が液滴化する時は、すべてのインクが液滴にはならないので、余分のインクの微少液滴が吐出口の周辺に付着することを皆無にすることは出来ないのである。従ってこれらが自発的に落下、吐出口内部に再吸引される、容易に排除されるならば、インク吐出への影響はなくなるのである。
【００８７】
本発明の含フッ素エポキシ樹脂組成物は、比較的低温でも硬化して、撥水撥油性、密着性、耐薬品性、耐摩擦性に優れた硬化物を提供することが可能となる。
【００８８】
図１、２に本発明の含フッ素エポキシ樹脂組成物を適用し得るインクジェット記録ヘッドの構成の１例の主要部を示す。図１は、流路に沿った断面図であり、図２は、斜視図である。
【００８９】
この記録ヘッド１３は、吐出エネルギー発生素子等が配置された基板１５上に、熱硬化性樹脂組成物及び／又は活性エネルギー線硬化性樹脂組成物の硬化物等を所定のパターンに成形して少なくとも流路を形成するようにした部材１４を積層接合した構成を有する。基板１５は、アルミナ等の放熱性の良い材料からなる基体２０の表面に、蓄熱層１９、金属で形成される発熱抵抗体層１８、アルミニウム等からなる電極１７ａ、１７ｂ及び保護層１６をこの順に積層した構成を有し、電極１７ａ、１７ｂに通電することによって、発熱抵抗体層１８の電極が積層されていない部分（ｎで示す領域内にある部分）に形成された吐出エネルギー発生素子が発熱し、その上方に位置する記録用液体に熱エネルギーが作用するようになっている。
【００９０】
記録に際して、記録用液体２１は、部材１４の流路端部微細開口である吐出口（オリフィス）２２まで充填され、その状態で、記録信号に対応して電極１７ａ、１７ｂに通電されると、ｎで示される領域が急激に発熱し、ここに接してる記録用液体２１に膜沸騰による気泡が発生し、その圧力で記録用液体２１が吐出口２２より小液滴２４となって吐出され、記録媒体２５に向かって飛翔する。
【００９１】
本発明のインクジェット記録ヘッドでは、吐出面２９の少なくとも吐出口開口部に含フッ素エポキシ樹脂組成物の硬化物が撥水、撥インク剤として適用され、この面に液滴が付着して液滴の吐出方向にずれが生じるのが防止される。しかも、含フッ素エポキシ樹脂組成物の硬化物は密着性に優れるだけでなく、記録用液体に有機溶剤、特に極性有機溶剤が含有されていてもそれによって撥水性や密着性が損なわれることがない。
【００９２】
尚、図２において、２６は吐出口、２７は液流路が形成された部材、２８は吐出エネルギー発生素子等が配設された基板、２９は吐出面である。
【００９３】
図３は、図２に示したようなマルチヘッドを組み込んだインクジェット記録装置の一例を示すものである。図３において、６１はワイピング部材としてのブレードであり、その一端はブレード保持部材によって保持されて固定端となり、カンチレバーの形態をなす。ブレード６１は、記録ヘッドより記録領域に隣接した位置に配設され、また、本例の場合、記録ヘッドの移動経路中に突出した形態で保持される。６２はキャップであり、ブレード６１に隣接するホームポジションに配設され、記録ヘッドの移動方向と垂直な方向に移動して吐出口と当接し、キャッピングを行う構成を備える。更に６３はブレード６１に隣接して設けられたインク吸収体であり、ブレード６１と同様、記録ヘッドの移動経路中に突出した形態で保持される。上記ブレード６１、キャップ６２、インク吸収体６３によって吐出回復部６４が構成され、ブレード６１及びインク吸収体６３によってインク吐出口面からの水分、塵埃等の除去が行われる。
【００９４】
６５はインクジェット方式により記録を行う記録ヘッドで、例えば図１、２で示したような熱エネルギーによってインクなどの記録用の液体を吐出する構成を有する。６６は記録ヘッド６５を搭載して記録ヘッド６５の移動を行う為のキャリッジである。キャリッジ６６はガイド軸６７と摺動可能に係合し、キャリッジ６６の一部はモーター６８によって駆動されるベルト６９と接続（不図示）している。これによりキャリッジ６６はガイド軸６７に沿った移動、即ち、記録ヘッド６５による記録領域及びその隣接した領域へ移動が可能となる。
【００９５】
５１は、記録媒体を挿入するための給紙部、５２は不図示のモーターにより駆動される紙送りローラーである。これらの構成によって記録ヘッドの吐出口面と対向する位置へ記録媒体が給紙され、記録が進行するにつれて排紙ローラ５３を介して排紙される。
【００９６】
上記構成において、記録ヘッド６５が記録終了時でホームポジションに戻る際、ヘッド回復部６４のキャップ６５は記録ヘッドの移動経路から退避しているが、ブレード６１は移動経路中に突出している。この結果、記録ヘッド６５の吐出口面がワイピングされる。また、キャップ６２が記録ヘッド６５の吐出口面に当接してキャッピングを行う際には、キャップ６２は記録ヘッドの移動経路中に突出するように移動する。
【００９７】
記録ヘッド６５がホームポジションから記録開始位置へ移動する場合、キャップ６２及びブレード６１は上述したワイピング時の位置と同一の位置にある。この結果、この移動においても記録ヘッド６５の吐出面はワイピングされる。
【００９８】
上述の記録ヘッドのホームポジションへの移動は、記録終了時や吐出回復時ばかりでなく、記録ヘッドが記録のための記録領域を移動する間に所定の間隔で記録領域に隣接したホームポジションへ移動し、この移動に伴って上記ワイピングが行われる。
【００９９】
インクジェット記録装置では、カラー記録の場合は、１ヘッド中に、シアン用、マゼンタ用、イエロー用及びブラック用の吐出口を並列した記録ヘッドを用いて行うことが出来る。また、各色の記録ヘッドを独立して並列して配設し用いてもよい。
【０１００】
これらの場合、各色の吐出は、１つの吐出口から行っても良いし、各色について同時に複数の吐出口から吐出を行って、２以上の同一色の液滴が記録媒体に同時に付着するようにしてもよい。
【０１０１】
本発明の記録ヘッドはこれまで説明した材料構成の撥インク処理材料によって表面処理がなされ、下記実施例に示されるような化学的な性質を有するので、インクジェットインクの付着が少なく、付着したインクがきわめて容易にクリーニング用ワイパーブレードにて除去される。よって印字の実質の持続性が飛躍的に高くなる。
【０１０２】
【実施例】
以下実施例にて本発明をさらに詳しく説明する。
【０１０３】
（実施例１〜１０）
前記した組成物例１〜１０のジエチレングリコールジメチルエーテル／トルエン混合溶媒（１：１）中への３０乃至４０重量％溶液を作成した。これを５μｍの厚さの熱酸化膜を有するシリコンウエファー基板上にウエットで１μｍ乃至３μｍの厚さにスピンナーを用いて塗布した。ついでこの基板を１１０℃のホットプレート上で５分乾燥し溶剤を除去した。この基板に高圧水銀灯を用いた紫外線照射装置にて２Ｊ／ｃｍ^２の積算量の紫外線を照射した。次に１５０℃の炉で１５分間加熱して硬化反応を完結させた。
【０１０４】
作成した基板を用いて以下の測定を実施した。
【０１０５】
Ｔ１：接触角の測定
純水、オレイン酸の１０重量％水溶液、グリセリン２０重量％水溶液、界面活性剤１重量％水溶液〔ポリオキシエチレンノニルフェニルエーテル：ＨＬＢ（Ｈｙｄｒｏｐｈｏｂｉｃ−Ｌｉｏｐｈｏｂｉｃ−Ｂａｌａｎｃｅ）＝１０〕の各液体を用いて静的接触角の測定を常温にて行った。
【０１０６】
Ｔ２：染料水溶液への浸せき後の接触角測定
水溶性染料ダイレクトブラック１６８の３重量％水溶液（ｐＨ＝１０．３）に撥インク処理した基板を６０℃で７日間浸せきした。その後この基板を純水にて洗浄、乾燥し、再度インクの接触角を測定した。
【０１０７】
Ｔ３
図４（ａ）に示すように、予め吐出エネルギー発生素子等が設けられた基材４１上にポジ型フォトレジスト４２（東京応化工業社製「ＰＭＥＲ・ＡＲ−９００」）を３０μｍになるようにスピンコートし、オーブン中で９０℃、４０分のプリベイクを行いレジスト層を形成した。その後、図４（ｂ），（ｃ）に示すようにマスク４３を用いてパターニングし、レジストパターン４を得た。該レジストパターン４４上に、図４（ｄ）に示すように流路形成用材料として、以下の組成の主剤に硬化剤（変性脂肪族アミン、富士化成工業社製「フジキュアーＦＸＫ８３０」）を、主剤／硬化剤＝１００／５０（重量比）で混合して、１００μｍの層厚で積層した。
【０１０８】
【表１】

【０１０９】
流路形成用材料層４５を積層後、２５℃、２４時間放置した後、更に１００℃、２時間の熱硬化処理を行った。次に、こうして得られた積層体を３重量％の水酸化ナトリウム水溶液に浸せきし、レジストパターン４４を溶解除去し、洗浄、乾燥させて液流路４６を形成し（図４（ｅ））、インクジェット記録ヘッドを得た。
【０１１０】
こうして得られたインクジェット記録ヘッドの吐出口面に、実施例１〜１０の含フッ素エポキシ樹脂組成物を個々に塗布し、これを８Ｊ／ｃｍ^２の紫外線露光及び１５０℃、１時間の加熱によって硬化させた。
【０１１１】
更に、このインクジェット記録ヘッドに所定の電気配線を行ってプリンタに組み込み、純水／グリセリン／フードブラック２（水溶性黒色染料）／Ｎ−メチルピロリドン＝７０／１５／３／１２（重量部）からなるインクジェット用インクを用いて長期印字耐久試験を行った。
【０１１２】
印字耐久試験は、文書と着弾精度を評価するパターンを１００枚印字して、最終の印字サンプルからドットの乱れを評価した。この結果をＴ３−１とした。
評価Ａ：ドット位置の乱れがなく、文字は鮮明である。
評価Ｂ：ドット位置の乱れが少々あるが、文字の品位への影響は軽微である。
評価Ｃ：ドット位置の乱れがかなりあり、文字も鮮明さが低下している。
評価Ｄ：ドットの欠け、文字品位の大幅な低下が発生している。
【０１１３】
また、使用した記録ヘッドの表面を観察し、インクの付着量を評価した。この結果をＴ３−２とした。
評価Ａ：吐出口表面にインク滴がほとんどない。
評価Ｂ：吐出口表面に小さいインク滴が見られる。
評価Ｃ：吐出口近傍に大きなインク滴がある。
【０１１４】
上記の結果を下記表２に整理した。
【０１１５】
（比較例１）
本発明の含フッ素エポキシ樹脂組成物に代えて、フッ素樹脂塗料（住友スリーエム社製「フロラード（Ｆｌｕｏｒａｄ）ＦＣ−７２２」）を用い、１００℃で３０分の乾燥を硬化条件として、上記実施例と同様に上記Ｔ１〜Ｔ３の評価を実施した。
【０１１６】
（比較例２）
含フッ素エポキシ樹脂である下記構造式Ｄ−１，Ｄ−２で表わされる化合物を用いた下記組成物を用いた以外は、実施例と同様の塗布、硬化条件にてテスト基板及び記録ヘッドを作製してＴ１〜Ｔ３の各評価を行った。
【０１１７】
【外２６】

【０１１８】
【表２】

【０１１９】
以上示したように、本発明の含フッ素エポキシ樹脂組成物からなる被膜は接触角が高く、かつその持続性において良好である。またインクが長期にわたって接触しても記録ヘッド表面におけるインクの付着がなく、結果としてドットの着弾精度が良く、印字品位を長く維持できるようになることがわかる。
【０１２０】
（実施例１２）
実施例１、３、６の各組成物をポリエーテルサルフォンの成形板にスピンナーにて、溶剤蒸発後の膜厚で約２μｍに塗布した。この基板に高圧水銀灯から合計１０Ｊ／ｃｍ^２の光を照射し、重合を行った。次いでこの基板にビーム径５μｍに収斂した波長１９５ｎｍのエキサイマーレーザー光を塗膜の上方から照射して、吐出口穴開け加工を行った。穴開けは良好に行われ、エッジ部の分解残渣が少ない加工状態であった。これより本発明の組成物は、紫外線レーザーによる加工にも優れた適性を有することがわかる。
【０１２１】
【発明の効果】
以上の説明より、本発明の含フッ素エポキシ樹脂組成物は、低温で硬化可能であり、密着性が良く所望のパターン形状の被膜が容易に形成し得ること、及び良好な撥水性を付与する表面改質処理が可能であることが理解される。よって、本発明によれば、吐出口に良好な撥インク性を有するインクジェット記録ヘッドを配し、高精度な印字が可能なインクジェット記録装置を提供することができる。
【図面の簡単な説明】
【図１】本発明を適用するインクジェット記録ヘッドの構成例の主要部断面図である。
【図２】図１のインクジェット記録ヘッドの主要部斜視図である。
【図３】図２のインクジェット記録ヘッドを組み込んだインクジェット記録装置の一例を示す図である。
【図４】本発明の実施例におけるインクジェット記録ヘッドの作製工程を示す図である。
【符号の説明】
１３ インクジェット記録ヘッド
１４ 液流路を形成した部材
１５ 基板
１６ 保護層
１７ａ，１７ｂ 電極
１８ 発熱抵抗体
１９ 蓄熱層
２０ 基体
２１ 記録用液体
２２ 吐出口
２３ 記録用液体のメニスカス
２４ 小液滴
２５ 記録媒体
２６ 吐出口
２７ 液流路が形成された部材
２８ 吐出エネルギー発生素子等が配設された基板
２９ 吐出面
４１ 基材
４２ ポジ型フォトレジスト
４３ マスク
４４ レジストパターン
４５ 液流路形成用材料
４６ 液流路
５１ 給紙部
５２ 紙送りローラー
５３ 排紙ローラー
６１ ブレード
６２ キャップ
６３ インク吸収体
６４ 吐出回復部
６５ 記録ヘッド
６６ キャリッジ
６７ ガイド軸
６８ モーター
６９ ベルト[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a polymerizable resin composition that can be treated with water and ink repellency in a desired pattern, particularly a resin composition that can be polymerized by ultraviolet irradiation to form a coating film in a desired pattern.ThingsThe present invention relates to a surface modification method used, an ink jet recording head subjected to ink repellent treatment using the composition, and an ink jet recording apparatus using the same.
[0002]
[Prior art]
In various fields, methods for obtaining these properties by applying water-repellent paints to members that require water resistance and ink repellency are generally known, and resin materials and paints used therefor have been developed. Yes.
[0003]
The most common water- and oil-repellent paints are fluorine resin and silicone resin paint. In other words, fluoroolefins and fluorine-based paints having a perfluoro group are extremely stable both thermally and chemically, have excellent weather resistance, water resistance, chemical resistance, solvent resistance, etc., and release properties. It is also excellent in friction resistance and water repellency and is widely used in various applications. Silicone resin is excellent in water and oil repellency, but because of its low hardness, it can be used in combination with or modified with other resin systems such as acrylic resin, epoxy resin, and urethane resin. Often composed.
[0004]
On the other hand, in an inkjet (liquid ejection) recording head that discharges liquid as a small droplet from an outlet and adheres to paper or the like to perform recording or image formation, the recording characteristics are smaller in order to achieve higher recording characteristics. Improvements in performance such as droplets, higher drive frequency, and higher number of outlets continue. Accordingly, surface treatment for making it easier to keep the discharge port surface always in the same surface state is becoming more and more important.
[0005]
However, it is difficult to use the existing water- and oil-repellent material as described above to selectively perform the surface treatment selectively or in a pattern shape so that the ink does not adhere to the discharge port surface. The reason is,
(1) In order to have the characteristics of a photoresist, it must be composed mainly of substances with photosensitive functional groups, but molecules are designed so that these compounds have water and ink repellency at the same time. This is not easy in terms of synthesis technology.
[0006]
Also,
(2) The surface treatment of the ink jet recording head needs to have a very thin film thickness of several μm or less so as not to disturb the function of the fine nozzle, but the existing paint should be controlled to such a film thickness. This is because it is difficult.
[0007]
When surface treatment is achieved with existing fluorine-based materials, it is necessary to design the coating film structure so that the surface properties can be maintained for a long time. However, most water- and oil-repellent materials have low coating hardness and poor friction durability, or when contamination occurs, the water- and oil-repellency tends to be low and difficult to recover. The exit surface treatment material is not always satisfactory.
[0008]
At the present time, it is desired that an ink ejection port used in an ink jet recording system that performs recording by ejecting ink as small droplets has the following performance.
[0009]
That is,
(1) The remaining ink in the form of droplets is quickly re-stored in the ejection port.
[0010]
(2) Ink droplets adhering to the surface should be easily swept away by a cleaning operation.
[0011]
(3) The ejection surface of the recording head has excellent scratch resistance during cleaning operations and paper conveyance.
[0012]
(4) In repeated droplet formation and ink refill, a meniscus is formed at the discharge port surface position.
[0013]
(5) The normal direction of the meniscus is the discharge direction.
[0014]
(6) The ink has a sufficient interfacial tension, that is, a contact angle enough to form a meniscus even in a low surface tension ink or in a low negative pressure state.
[0015]
(7) The inkjet recording liquid is often adjusted to a basic pH of 7 to 11 for dissolution stability, and a structural material excellent in alkali resistance and hydrolyzability of the member is employed.
[0016]
The reason why these various required performances are required is that, in an ink jet recording head, if a recording liquid such as ink adheres to the periphery of the ejection port, it is displaced in the ejection (flight) direction of the liquid droplets ejected from the ejection port. This is because it is directly related to the printing performance in which high-precision printing cannot be performed.
[0017]
Prior arts related to the present invention include: lacquer type fluororesin paint, fluorine type ultraviolet curable paint, thermosetting type fluororesin paint, fluorine type silane coupling agent, epoxy resin composition in which fluororesin particles are dispersed, gas layer There is a paint that discloses polymerizing a resin thin film to form a film.
[0018]
For example, JP-A-2-39944 discloses performing a polymer ink repellent treatment having a fluoroacetyl group and a silazane group.
[0019]
However, for these coating materials, the water repellency and the durability of the coating film may not always be compatible. Japanese Patent Application Laid-Open No. 3-7781 discloses an ink repellent treatment agent that uses glycidyl ether derived from a fluorine-based diol. Since the fluorine-based epoxy resin disclosed here is cured and used, the durability of the coating film is good, but the ink repellency is not sufficiently satisfactory.
[0020]
Japanese Laid-Open Patent Publication No. 6-328698 discloses a method and material for drilling with an excimer laser which is a disintegrating active energy ray. Although the method disclosed here can achieve excellent processing accuracy and is useful for manufacturing an inkjet recording head suitable for this, ink repellent treatment using a photolithography method for performing more precise processing. Application is difficult.
[0021]
[Problems to be solved by the invention]
In this way, when conventional materials and methods are used, precision is required, and durable water and ink repellant surface treatments are not sufficiently satisfactory, and there is room for improvement. The fact is that there is.
[0023]
  The present inventionEyesThe targetA resin composition for water-repellent treatment having the various performances described above as a coating film,Fluorine-containing epoxy resin composition suitable as a water repellent or water repellent coating applied to a place where there is an opportunity to come into contact with a solution or substance containing a component that impairs the film formability and adhesion of the water repellent such as a polar organic solventForInk jet recording head having good ink repellency and ink jet recording apparatus using the headAnd surface treatment methodIs to provide.
[0024]
[Means for Solving the Problems]
  Main departureTomorrow,In an inkjet recording head having a discharge port for discharging a recording liquid,Fluorine-containing epoxy resin having one or more perfluoroalkyl groups having 6 to 12 carbon atoms and two or more alicyclic epoxy groups in one moleculeAndThion polymerization catalystWhenContains at leastA cured film obtained by curing the fluorine-containing epoxy resin composition is formedIt is characterized byAn ink jet recording apparatus comprising: an ink jet recording head; and the ink jet recording head and a carriage that moves the recording head.is there. In the present invention, the “perfluoroalkyl group” means a group in which all hydrogen atoms in the alkyl group are substituted with fluorine.
[0025]
As the fluorine-containing epoxy resin used in the present invention, an epoxy compound represented by the following general formula (A-1) is preferably used.
[0026]
[Outside 7]

R is an aliphatic residue that binds a monomer having an alicyclic epoxy group.
[0027]
Moreover, as said fluorine-containing epoxy resin used for this invention, the epoxy compound represented by the following general formula (A-2) is used preferably.
[0028]
[Outside 8]

[0029]
Moreover, as said fluorine-containing epoxy resin used for this invention, the epoxy polymer represented by the following general formula (A-3) is used preferably.
[0030]
[Outside 9]

[0031]
Moreover, as said fluorine-containing epoxy resin used for this invention, the epoxy polymer represented by the following general formula (A-4) is used preferably.
[0032]
[Outside 10]

[0033]
Moreover, as said fluorine-containing epoxy resin used for this invention, the epoxy polymer represented by the following general formula (A-5) is used preferably.
[0034]
[Outside 11]

[0035]
If necessary, the fluorine-containing epoxy resin composition of the present invention can further contain at least one compound represented by the following general formula (C-1) or (C-2) as a compatibilizing agent. .
[0036]
[Outside 12]

[0037]
  Also,Main departureTomorrowFirst step of applying and drying the fluorine-containing epoxy resin composition of the present invention on a substrate, second step of irradiating active energy rays in a pattern through a mask, a liquid capable of dissolving the composition The surface is selectively surface-treated in the order of the third step of dissolving and removing the non-irradiated portion of the active energy ray and the fourth step of applying post-cure as necessary. Processing methodsois there.
[0038]
  Also,Main departureTomorrowA first step of applying and drying the fluorine-containing epoxy resin composition of the present invention on a substrate, a second step of polymerizing and curing the entire surface of the composition by irradiation with heat or active energy rays, a disintegrating activity Selectively to the base material in the order of a third step of selectively removing the cured composition by selectively irradiating energy rays, and a fourth step of post-curing as necessary. Surface treatment method characterized by performing surface treatment onsois there.
[0040]
Since the resin composition of the present invention is based on an epoxy resin, it can provide a cured product that has excellent adhesion to various members, can be cured at a relatively low temperature, and has excellent physical properties as a structure. Furthermore, since an epoxy compound having a perfluoro group at the terminal is contained, resistance to water-soluble organic solvents, particularly polar organic solvents, is greatly improved. And the compatibilization between components can be given by the action of the compatibilizing agent, and the range of the material composition can be widened.
[0041]
The fluorine-containing epoxy resin composition of the present invention is useful as a material to be applied to a place where there is a chance of contact with a solution or substance containing a component that impairs the adhesion of the water repellent, such as a polar organic solvent. As a water repellent or water repellent paint used in such a place, it is particularly suitable for water repellency and ink repellency treatments on the discharge port surface of an ink jet recording head.
[0042]
In the ink jet recording apparatus of the present invention, it is excellent in processing accuracy by using selective surface modification utilizing photopolymerizability, and since a cured film is formed using a specific material, solid strength, friction strength, It has an excellent water-repellent or ink-repellent part.
[0043]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
[0044]
The fluorine-containing epoxy resin used in the fluorine-containing epoxy resin composition of the present invention has one or more perfluoroalkyl groups and two or more epoxy groups in one minute, and even if the epoxy group reacts, the molecule Since there is a perfluoroalkyl group on the relatively outer side, the surface of the resin maintains a high density of fluorine atoms. It is considered that this makes it possible to form a layer having water repellency, oil repellency, and ink repellency on the surface while the inside is a hard resin layer.
[0045]
In the present invention, the fluorine-containing epoxy resin is preferably an epoxy compound represented by the following general formulas (A-1) to (A-2) or an epoxy represented by (A-3) to (A-5). At least one polymer is preferably used. Here, the epoxy compound refers to a compound made of an oligomer, and the epoxy polymer refers to a polymer excluding the oligomer.
[0046]
[Outside 13]

R is an aliphatic residue that binds a monomer having an alicyclic epoxy group.
[0047]
[Outside 14]

[0048]
[Outside 15]

[0049]
Among these, the epoxy polymer represented by the general formula (A-3) has low polymerizability, but since it does not have an ester group, it is expected to be a coating film excellent in water resistance and hydrolyzability.
[0050]
Moreover, the application | coating suitability of a composition is improved by using an epoxy compound together with the epoxy polymer which is a high polymer, the drying property after solvent evaporation is improved, and the workability | operativity as a dry coating film is improved. That is, the epoxy compound functions as a binder. Therefore, it is preferable to use an epoxy compound in combination in performing a pattern exposure operation. In this case, the ratio of the two may be appropriately determined in consideration of the respective softening point and glass transition temperature, but a range of epoxy compound: epoxy polymer = 10: 90 to 90:10 (weight ratio) is preferable.
[0051]
Specific examples of the compound represented by the general formula (A-1) include the following compounds.
[0052]
[Outside 16]

[0053]
Specific examples of the compound represented by the general formula (A-2) include the following compounds.
[0054]
[Outside 17]

[0055]
Specific examples of the compound represented by the general formula (A-3) include the following compounds.
[0056]
[Outside 18]

A vinyl polymer (A-3-1) having a number average molecular weight of 6000 obtained by polymerization.
[0057]
[Outside 19]

A vinyl polymer (A-3-2) having a number average molecular weight of 8,000 obtained by polymerization.
[0058]
Moreover, as a specific example of a compound represented by the said general formula (A-4), the following compound is mentioned, for example.
[0059]
[Outside 20]

[0060]
Moreover, as a specific example of a compound represented by the said general formula (A-5), the following compound is mentioned, for example.
[0061]
[Outside 21]

[0062]
The epoxy resin composition of the present invention contains a cationic polymerization catalyst (polymerization initiator) as a catalyst for curing the epoxy resin composition. The compound used for such purposes is selected from substances known as curing agents for epoxy resins. Since the composition of the present invention is an epoxy resin composition, aromatic and aliphatic amines and acid anhydrides can be added and polymerized by heat curing. However, in the present invention, it is specifically designed to be highly reactive with an onium salt of Lewis acid activated by active energy rays that can be cured at low temperature, and surface treatment is selectively performed by photolithography. For this purpose, it is suitable for surface modification of a substrate that is difficult to keep at a high temperature. The cationic polymerization catalyst used in the present invention is preferably a bis (4-tert-butylphenyl) iodonium salt, “Optoma-SP-150” or “Optoma-SP170” (produced by Asahi Denka Kogyo Co., Ltd.) represented by the following structural formula. Etc.
[0063]
[Outside 22]

[0064]
Further, “Irgacure 261” (manufactured by Ciba Specialty Co., Ltd.) represented by the following structural formula can be used.
[0065]
[Outside 23]

[0066]
If necessary, the fluorine-containing epoxy resin composition of the present invention may further contain at least one compound represented by the following general formula (C-1) or (C-2) as a compatibilizing agent. .
[0067]
[Outside 24]

[0068]
Specific examples of the compatibilizer include compounds represented by the following structural formulas, for example.
[0069]
[Outside 25]

[0070]
The compatibilizing agent has a fluorine atom but mainly contains a fluoromethyl group, and has a short chain length. Therefore, the surface energy lowering action as a molecule is small, and the water repellency and ink repellency are not large. However, it is effective for enhancing the compatibility between the fluorine-containing epoxy resin and the cationic polymerization catalyst. That is, when the compatibilizer is used in combination with the present invention, the onium salt of Lewis acid, which is a cationic polymerization catalyst, has high polarity, so it has poor compatibility with the fluorine-containing epoxy resin used, and leveling properties during coating It is necessary to overcome practical difficulties such as difficult to obtain.
[0071]
The epoxy resin composition of the present invention basically comprises
A: Fluorine-containing epoxy resin
B: Cationic polymerization catalyst, and as required
C: compatibilizer,
Containing. Preferred blending ratios of these components A, B, and C in the composition are as follows.
[0072]
Component B is 0.1 parts by weight with respect to 100 parts by weight of the total amount of the epoxy resin component (component A when component C is not used and component A and component C when component C is used in combination). It is the range of thru | or 10 weight part. The range of the ratio is the layer thickness, the required pattern precision, the degree of crosslinking of the polymerized coating, the development stability when developing, the reaction rate when only curing is performed, It is determined from factors such as. The usual use amount of the cationic polymerization catalyst in consideration of such factors is 0.1 to 7 parts by weight, more preferably 0.3 to 5 parts by weight with respect to 100 parts by weight of the total amount of the epoxy resin components. is there.
[0073]
When the component C as a compatibilizer is used in combination, the range is component A: component C = 100: 10 to 100: 100 (weight ratio). That is, the component A must be 50% by weight or more in the epoxy resin component.
[0074]
  The structural example of the composition of this invention is illustrated below. The following ratio indicates the weight ratio of the solid content.
(Composition Example 1) A-1-1: B-1 = 96: 4
(Composition Example 2) A-1-2: B-1 = 94: 6
(Composition Example 3) A-2-1: A-3-1: B-2 = 48: 48: 4
(Composition Example 4) A-2-2: A-4-1: B-1 = 30: 63: 7
(Composition Example 5) A-1-1: A-5-1: B-2 = 35: 60: 5
(Composition Example 6) A-1-2: A-4-2: B-1: C-1 (p = 1 = 90: 10: 25: 4
(Composition Example 7) A-2-1: A-3-2: B-1: C-2 (q = 1 = 25: 55: 20: 1)
(Composition Example 8) A-2-2: A-5-1: B-1: C-2 (q = 1 = 25: 45: 30: 0.5
(Composition Example 9) A-2-1: B-1 = 94: 6
(Composition Example 10) A-2-2: B-1 = 97:3
[0075]
Other polymers can be added to the fluorine-containing epoxy resin composition of the present invention as necessary. For example, it provides the function of improving the workability as a dry coating film that improves the applicability of the composition of the present invention and increases the drying property after evaporation of the solvent, and a polymer that functions as a binder can be used. The combined use of such a binder substance is preferable when the composition of the present invention is exposed in a pattern to obtain a desired pattern shape.
[0076]
The binder polymer that can be added to the fluorine-containing epoxy resin composition of the present invention includes an alicyclic epoxy resin oligomer, an acrylic resin copolymerized with an acrylic monomer having no fluorine atom group but having an epoxy group in the side chain, A vinyl polymer obtained by polymerizing a vinyl monomer having an alicyclic hydrocarbon group having an epoxy group in a chain, a polyether polymer having an alicyclic hydrocarbon group having an epoxy group in a side chain (for example, “EHPE3150 manufactured by Daicel Chemical Industries, Ltd. ")" Is optimal as an epoxy polymer which itself can participate in the crosslinking reaction. When such a polymer having no epoxy group is used, it is selected with the intention of adjusting the physical properties according to the application to which it is applied. Such materials include, for example, “PKHC” and “PKHJ”, which are polymers of bisphenol-type epoxy resins, ethylene / vinyl acetate copolymers, phenol resins, polycarbonate resins, polyester resins, polyamide resins, soluble General-purpose polymer compounds for paint such as polyimide resin can be used.
[0077]
In the composition of the present invention, when such other polymer is used in combination, the weight ratio of Component A to Component C is as follows: Component A: Component C = 100: 10 to 100: 100 (weight ratio) It is. Component B is contained in a proportion of 0.1 to 10 parts by weight in the total amount (100 parts by weight) of the composition containing the binder polymer.
[0078]
The method is illustrated about the specific method at the time of using a composition in this invention. When performing active energy ray curing, as described above, a cationic photopolymerization catalyst that releases a Lewis acid by light is added and used as a catalyst. When heat-curing, a Lewis acid such as boron trifluoride amine catalyst may be added and used.
[0079]
<Coating film formation method>
The fluorine-containing epoxy resin composition of the present invention is used in a state of being dissolved in an organic solvent such as an aromatic, aliphatic hydrocarbon, ester, ether, or fluorine solvent. When the coating film thickness is as small as several μm, a normal precision coating apparatus such as a roll coater, a spin coater, or a spray coater can be used.
[0080]
The first method of applying a surface treatment to the pattern is the first step of applying the fluorine-containing epoxy resin composition of the present invention to a substrate (object to be treated) and drying, patterning active energy rays using a mask. A second step of selectively curing the composition by irradiating in the shape, and then a third step of dissolving and removing the non-irradiated part of the active energy rays in the second step by a development process using a developer, This is achieved by sequentially performing. The basic process is the same as that of photolithography, but it is necessary to select a solvent suitable for the resin composition as the developer. As the developer, aromatic hydrocarbons, ketones, esters, glycol ethers, and mixtures thereof are used. In order to complete the reaction of the resin composition, it is desirable to further carry out heating and irradiation with active energy rays (fourth step) after development.
[0081]
The second method of applying a surface treatment to the pattern is the first step in which the fluorine-containing epoxy resin composition of the present invention is applied to a substrate and then dried, and is cured by irradiation with heat or active energy rays that promote polymerization. The second step is performed by sequentially performing a third step of irradiating a disintegrating active energy ray so as to selectively remove a desired portion of the cured portion.
[0082]
In order to complete the reaction also in the second method, it is desirable to perform heat treatment and irradiation with a polymerizable active energy ray (fourth step) at any stage.
[0083]
As the active energy ray for promoting the polymerization, an ultraviolet ray source containing abundant light having a wavelength of 250 to 480 nm is used. As the disintegrating active energy ray, light having a wavelength of 210 nm or less, an excimer laser, or the like is used.
[0084]
Thus, the fluorine-containing epoxy resin composition of the present invention can be applied to a place where there is an opportunity to contact a solution or substance containing a component that impairs the adhesion of the water repellent, such as a polar organic solvent. Further, as the water-based paint, water repellency, ink repellency, and treatment of the discharge port surface of the ink jet recording head can be suitably performed.
[0085]
According to the surface modification method of the present invention, the water repellent and oil repellent treatment excellent in adhesion to the substrate and surface hardness can be performed, so that the modification excellent in durability can be performed.
[0086]
As an application in an ink jet recording head, the surface of the discharge port is treated with the composition of the present invention, so that a strong surface of ink is not formed and a surface with good releasability that can be easily wiped off by a cleaning process is formed. The Many of the cleaning mechanisms mounted on the ink jet recording head include wiping with a rubber blade, sucking with a pump, and empty ejection at a position outside the recording paper. However, in any of these methods, when the ink column pulled out by the discharge pressure turns into droplets, all the ink does not become droplets, so extra small ink droplets adhere to the periphery of the discharge port. You can't make nothing to do. Therefore, if they are spontaneously dropped, re-sucked into the discharge port, and easily eliminated, the ink discharge is not affected.
[0087]
The fluorine-containing epoxy resin composition of the present invention can be cured even at a relatively low temperature, and can provide a cured product excellent in water / oil repellency, adhesion, chemical resistance and friction resistance.
[0088]
1 and 2 show the main part of an example of the configuration of an ink jet recording head to which the fluorine-containing epoxy resin composition of the present invention can be applied. FIG. 1 is a cross-sectional view along the flow path, and FIG. 2 is a perspective view.
[0089]
This recording head 13 is formed by molding a thermosetting resin composition and / or a cured product of an active energy ray curable resin composition into a predetermined pattern on a substrate 15 on which ejection energy generating elements and the like are arranged. It has the structure which laminated | stacked and joined the member 14 which formed the flow path. The substrate 15 has a heat storage layer 19, a heating resistor layer 18 made of metal, electrodes 17a and 17b made of aluminum, and a protective layer 16 in this order on the surface of a base 20 made of a material with good heat dissipation such as alumina. When the electrodes 17a and 17b are energized, the discharge energy generating element formed in the part where the electrode of the heating resistor layer 18 is not laminated (the part in the area indicated by n) generates heat. However, thermal energy acts on the recording liquid located above the recording liquid.
[0090]
At the time of recording, the recording liquid 21 is filled up to the discharge port (orifice) 22 which is a fine opening at the flow path end of the member 14, and in this state, when the electrodes 17a and 17b are energized corresponding to the recording signal, The region indicated by n suddenly generates heat, bubbles are generated by film boiling in the recording liquid 21 in contact therewith, and the recording liquid 21 is discharged as small droplets 24 from the discharge port 22 by the pressure. Fly toward the recording medium 25.
[0091]
In the ink jet recording head of the present invention, a cured product of the fluorine-containing epoxy resin composition is applied as a water repellent and ink repellent agent at least on the discharge port opening of the discharge surface 29, and droplets adhere to this surface and the droplets It is possible to prevent a deviation in the discharge direction. Moreover, the cured product of the fluorine-containing epoxy resin composition is not only excellent in adhesion, but even if the recording liquid contains an organic solvent, particularly a polar organic solvent, water repellency and adhesion are not impaired thereby. .
[0092]
In FIG. 2, 26 is a discharge port, 27 is a member in which a liquid flow path is formed, 28 is a substrate on which discharge energy generating elements and the like are disposed, and 29 is a discharge surface.
[0093]
FIG. 3 shows an example of an ink jet recording apparatus incorporating a multi-head as shown in FIG. In FIG. 3, reference numeral 61 denotes a blade as a wiping member, one end of which is held by a blade holding member to become a fixed end, and forms a cantilever. The blade 61 is disposed at a position adjacent to the recording area from the recording head, and in this example, is held in a form protruding in the moving path of the recording head. Reference numeral 62 denotes a cap, which is disposed at a home position adjacent to the blade 61 and has a configuration in which capping is performed by moving in a direction perpendicular to the moving direction of the recording head and contacting the discharge port. Further, reference numeral 63 denotes an ink absorber provided adjacent to the blade 61 and, like the blade 61, is held in a form protruding in the moving path of the recording head. The blade 61, the cap 62, and the ink absorber 63 constitute a discharge recovery portion 64, and the blade 61 and the ink absorber 63 remove moisture, dust, and the like from the ink discharge port surface.
[0094]
Reference numeral 65 denotes a recording head that performs recording by an ink jet method, and has a configuration in which a recording liquid such as ink is ejected by thermal energy as shown in FIGS. Reference numeral 66 denotes a carriage for mounting the recording head 65 to move the recording head 65. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected to a belt 69 (not shown) driven by a motor 68. As a result, the carriage 66 can move along the guide shaft 67, that is, move to the recording area by the recording head 65 and the adjacent area.
[0095]
51 is a paper feed unit for inserting a recording medium, and 52 is a paper feed roller driven by a motor (not shown). With these configurations, the recording medium is fed to a position facing the ejection port surface of the recording head, and is discharged through the discharge roller 53 as recording progresses.
[0096]
In the above configuration, when the recording head 65 returns to the home position at the end of recording, the cap 65 of the head recovery unit 64 is retracted from the moving path of the recording head, but the blade 61 protrudes into the moving path. As a result, the ejection port surface of the recording head 65 is wiped. Further, when the cap 62 performs capping by contacting the ejection port surface of the recording head 65, the cap 62 moves so as to protrude into the moving path of the recording head.
[0097]
When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are in the same position as the above-described wiping position. As a result, even in this movement, the ejection surface of the recording head 65 is wiped.
[0098]
The above-mentioned movement of the recording head to the home position is not only at the end of recording or at the time of ejection recovery, but also to the home position adjacent to the recording area at a predetermined interval while the recording head moves through the recording area for recording. Then, the wiping is performed with this movement.
[0099]
In an ink jet recording apparatus, color recording can be performed using a recording head in which discharge ports for cyan, magenta, yellow, and black are arranged in one head. Further, the recording heads for each color may be arranged and used independently in parallel.
[0100]
In these cases, each color may be ejected from a single ejection port, or each color may be ejected from a plurality of ejection ports at the same time, so that two or more same color droplets adhere to the recording medium simultaneously. May be.
[0101]
The recording head of the present invention is surface-treated with the ink repellent treatment material having the material structure described so far, and has the chemical properties as shown in the following examples. It is very easily removed with a wiper blade for cleaning. Therefore, the actual sustainability of printing is dramatically increased.
[0102]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples.
[0103]
  (Examples 1-10)
  Composition examples 1 to 1 described above0Of 30 to 40% by weight in a diethylene glycol dimethyl ether / toluene mixed solvent (1: 1). This was applied on a silicon wafer substrate having a thermal oxide film having a thickness of 5 μm by a wet to a thickness of 1 μm to 3 μm using a spinner. The substrate was then dried on a hot plate at 110 ° C. for 5 minutes to remove the solvent. This substrate is 2 J / cm with an ultraviolet irradiation device using a high-pressure mercury lamp.²The amount of UV rays was irradiated. Next, it was heated in a furnace at 150 ° C. for 15 minutes to complete the curing reaction.
[0104]
The following measurements were performed using the prepared substrate.
[0105]
T1: Measurement of contact angle
Pure water, 10% by weight aqueous solution of oleic acid, 20% by weight aqueous solution of glycerin, 1% by weight aqueous solution of surfactant [polyoxyethylene nonylphenyl ether: HLB (Hydrophobic-Liphophobic-Balance) = 10] The contact angle was measured at room temperature.
[0106]
T2: Contact angle measurement after immersion in dye aqueous solution
A substrate treated with ink repellent in a 3% by weight aqueous solution of water-soluble dye direct black 168 (pH = 10.3) was immersed at 60 ° C. for 7 days. Thereafter, the substrate was washed with pure water, dried, and the contact angle of the ink was measured again.
[0107]
T3
As shown in FIG. 4A, a positive photoresist 42 (“PMER AR-900” manufactured by Tokyo Ohka Kogyo Co., Ltd.) is 30 μm on a substrate 41 on which ejection energy generating elements and the like are previously provided. A resist layer was formed by spin coating and prebaking in an oven at 90 ° C. for 40 minutes. Thereafter, as shown in FIGS. 4B and 4C, patterning was performed using a mask 43, whereby a resist pattern 4 was obtained. On the resist pattern 44, as shown in FIG. 4 (d), a curing agent (modified aliphatic amine, “Fuji Cure FXK830” manufactured by Fuji Kasei Kogyo Co., Ltd.) is used as a flow path forming material. / Curing agent = 100/50 (weight ratio) was mixed and laminated with a layer thickness of 100 μm.
[0108]
[Table 1]

[0109]
After laminating the flow path forming material layer 45, it was allowed to stand at 25 ° C. for 24 hours, and further subjected to thermosetting treatment at 100 ° C. for 2 hours. Next, the laminate thus obtained is immersed in a 3% by weight aqueous sodium hydroxide solution, the resist pattern 44 is dissolved and removed, washed and dried to form a liquid flow path 46 (FIG. 4 (e)), An ink jet recording head was obtained.
[0110]
  Examples 1 to 1 were formed on the ejection port surface of the ink jet recording head thus obtained.0Each of the fluorine-containing epoxy resin compositions was applied individually, and this was applied at 8 J / cm.²The film was cured by UV exposure and heating at 150 ° C. for 1 hour.
[0111]
Furthermore, predetermined electrical wiring is performed on this ink jet recording head and incorporated in a printer. From pure water / glycerin / food black 2 (water-soluble black dye) / N-methylpyrrolidone = 70/15/3/12 (parts by weight) A long-term printing durability test was performed using the inkjet ink.
[0112]
In the printing endurance test, 100 patterns for evaluating the document and landing accuracy were printed, and dot disturbance was evaluated from the final print sample. This result was designated as T3-1.
Evaluation A: The dot position is not disturbed and the characters are clear.
Evaluation B: Although the dot position is slightly disturbed, the influence on the quality of characters is slight.
Evaluation C: The dot position is considerably disturbed, and the character is also less clear.
Evaluation D: The lack of dots and a significant reduction in character quality occur.
[0113]
Further, the surface of the used recording head was observed to evaluate the ink adhesion amount. This result was designated as T3-2.
Evaluation A: There are almost no ink droplets on the discharge port surface.
Evaluation B: Small ink droplets are observed on the discharge port surface.
Evaluation C: There is a large ink droplet in the vicinity of the ejection opening.
[0114]
The above results are summarized in Table 2 below.
[0115]
(Comparative Example 1)
Instead of the fluorine-containing epoxy resin composition of the present invention, a fluororesin paint (“Fluorad FC-722” manufactured by Sumitomo 3M) was used, and the drying was performed at 100 ° C. for 30 minutes as curing conditions. Similarly, evaluation of the above T1 to T3 was performed.
[0116]
(Comparative Example 2)
A test substrate and a recording head were prepared under the same coating and curing conditions as in the examples except that the following composition using the compounds represented by the following structural formulas D-1 and D-2, which are fluorine-containing epoxy resins, was used. Then, each evaluation of T1 to T3 was performed.
[0117]
[Outside 26]

[0118]
[Table 2]

[0119]
As described above, the film made of the fluorine-containing epoxy resin composition of the present invention has a high contact angle and good durability. Further, it can be seen that even when the ink contacts for a long time, the ink does not adhere to the surface of the recording head, and as a result, the dot landing accuracy is good and the printing quality can be maintained for a long time.
[0120]
  (Example 12)
  Examples 1, 3,6'sEach composition was applied to a polyethersulfone molding plate with a spinner so that the film thickness after solvent evaporation was about 2 μm. A total of 10 J / cm from this high-pressure mercury lamp²The polymerization was performed by irradiating the light. Next, an excimer laser beam having a wavelength of 195 nm converged to a beam diameter of 5 μm was irradiated onto the substrate from above the coating film, thereby performing discharge port drilling. Drilling was performed satisfactorily, and there was little decomposition residue at the edge. This shows that the composition of the present invention has excellent suitability for processing by an ultraviolet laser.
[0121]
【The invention's effect】
From the above description, the fluorine-containing epoxy resin composition of the present invention can be cured at a low temperature, can easily form a film having a desired pattern shape with good adhesion, and provides a surface with good water repellency. It will be appreciated that a modification process is possible. Therefore, according to the present invention, it is possible to provide an ink jet recording apparatus in which an ink jet recording head having good ink repellency is arranged at the ejection port and capable of performing highly accurate printing.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part of a configuration example of an ink jet recording head to which the present invention is applied.
FIG. 2 is a perspective view of a main part of the ink jet recording head of FIG.
FIG. 3 is a diagram illustrating an example of an ink jet recording apparatus in which the ink jet recording head of FIG. 2 is incorporated.
FIG. 4 is a diagram showing a manufacturing process of an ink jet recording head in an embodiment of the present invention.
[Explanation of symbols]
13 Inkjet recording head
14 Member with liquid flow path
15 substrate
16 Protective layer
17a, 17b electrode
18 Heating resistor
19 Heat storage layer
20 substrate
21 Recording liquid
22 Discharge port
23 Meniscus of recording liquid
24 small droplets
25 Recording media
26 Discharge port
27 Member in which liquid flow path is formed
28 Substrate on which discharge energy generating elements are arranged
29 Discharge surface
41 Base material
42 positive photoresist
43 Mask
44 resist pattern
45 Liquid flow path forming material
46 Liquid flow path
51 Paper feeder
52 Paper feed roller
53 Paper discharge roller
61 blade
62 cap
63 Ink absorber
64 Discharge recovery section
65 Recording head
66 Carriage
67 Guide shaft
68 motor
69 belt

Claims (6)

In an ink jet recording head having a discharge port for discharging a recording liquid, one or more perfluoroalkyl groups having 6 to 12 carbon atoms and two or more alicyclic epoxy groups in one molecule are formed on the discharge port surface. An inkjet recording head having a cured film formed by curing a fluorine-containing epoxy resin composition containing at least a fluorine-containing epoxy resin and a cationic polymerization catalyst ,
The fluorine-containing epoxy resin has a structure represented by at least one formula selected from the group consisting of the following general formulas (A-1), (A-3) and (A-4). head.
[Outside 1]

R is an aliphatic residue that binds a monomer having an alicyclic epoxy group.
[Outside 3]

[Outside 4]

The fluorine-containing epoxy resin composition, an ink jet recording head according to claim 1 that have a structure represented by the general formula (A-1). The fluorine-containing epoxy resin composition, an ink jet recording head according to claim 1 that have a structure represented by the general formula (A- 3). The fluorine-containing epoxy resin composition, an ink jet recording head according to claim 1 that have a structure represented by the general formula (A- 4). Furthermore, the inkjet recording head in any one of Claims 1-4 which contains at least 1 sort (s) of the compound represented by the following general formula (C-1) or (C-2) as a compatibilizing agent.
[Outside 6]

An ink jet recording apparatus characterized by comprising a carriage for moving the ink jet recording head and the recording head according to any one of claims 1-5.

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